ISSN (print) 1995-2732
ISSN (online) 2412-9003

 

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Abstract

Problem Statement (Relevance): Molybdenum is a refractory and corrosion-resistant metal that is widely used in the production of alloyed steels, as well as acid-resistant and heat-resistant alloys. Nano-molybdenum offers an even wider range of applications, which include heat- and acid-resistant alloys with enhanced corrosion and physical properties; lubricants; as a catalyst; coatings and polymers [1-3]. Objectives: The authors of this research aim to look at how nanodispersed molybdenum powder can be produced in an industrial plasma reactor. Methods Applied: The following state-of-the-art techniques were used for the purposes of this research: mathematical modeling and thermodynamic calculations, hydrodynamic and thermal similarity, calorimetry probe and diagnostics, chemical and physical analyses, X-ray diffraction, infrared spectroscopy, chromatography, high-temperature pulse extraction, thermogravimetry, thermal desorption mass spectrometry, low-temperature adsorption, transmission and scanning electron microscopy. Originality: The authors studied the thermal, process and performance characteristics of a 150kW industrial three-jet direct-flow plasma reactor. Findings: A close-to-optimum combination of the thermal efficiency, the specific enthalpy of the orifice gas and its mass flow rate can be achieved if the reactor power is 150 kW. The bulk temperature of the plasma flow in a plasma reactor of length 12 insulated with a 0.005 m zirconia cylinder varies between 5,500 K and 2,450 K. The specific output reaches 1,214 MW/m3. The design life of the electrodes is 4,700 hours for a copper anode and 111 hours for a tungsten cathode. The expected contamination of carbides and borides with the products of electrode erosion does not exceed 0.0001% of copper and 0.00002% of tungsten. The authors established the possibility of obtaining nanodispersed molybdenum powder in a plasma nitrogen flow in the temperature range of 5,273 K to 2,800 K.

Keywords

Plasma reactor, plasma, nanopowder, molybdenum.

Lyudmila S. Shiryaeva – Ph.D. (Eng.), Associate Professor

Siberian State Industrial University, Novokuznetsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Viktoria V. Rudneva – D.Sc. (Eng.), Professor

Siberian State Industrial University, Novokuznetsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Gennady V. Galevsky - D.Sc. (Eng.), Professor

Siberian State Industrial University, Novokuznetsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

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